public AggregateType GetAggregate(AggregateSymbol agg, AggregateType atsOuter, TypeArray typeArgs)
{
Debug.Assert(agg.GetTypeManager() == this);
Debug.Assert(atsOuter == null || atsOuter.getAggregate() == agg.Parent, "");
if (typeArgs == null)
{
typeArgs = BSYMMGR.EmptyTypeArray();
}
Debug.Assert(agg.GetTypeVars().Count == typeArgs.Count);
AggregateType pAggregate = _typeTable.LookupAggregate(agg, atsOuter, typeArgs);
if (pAggregate == null)
{
pAggregate = _typeFactory.CreateAggregateType(
agg,
typeArgs,
atsOuter
);
Debug.Assert(!pAggregate.fConstraintsChecked && !pAggregate.fConstraintError);
_typeTable.InsertAggregate(agg, atsOuter, typeArgs, pAggregate);
}
Debug.Assert(pAggregate.getAggregate() == agg);
Debug.Assert(pAggregate.GetTypeArgsThis() != null && pAggregate.GetTypeArgsAll() != null);
Debug.Assert(pAggregate.GetTypeArgsThis() == typeArgs);
return(pAggregate);
}
public void SetTypeArgsThis(TypeArray pTypeArgsThis)
{
TypeArray pOuterTypeArgs;
if (outerType != null)
{
Debug.Assert(outerType.GetTypeArgsThis() != null);
Debug.Assert(outerType.GetTypeArgsAll() != null);
pOuterTypeArgs = outerType.GetTypeArgsAll();
}
else
{
pOuterTypeArgs = BSYMMGR.EmptyTypeArray();
}
Debug.Assert(pTypeArgsThis != null);
_pTypeArgsThis = pTypeArgsThis;
SetTypeArgsAll(pOuterTypeArgs);
}
public AggregateType GetAggregate(AggregateSymbol agg, AggregateType atsOuter, TypeArray typeArgs)
{
Debug.Assert(agg.GetTypeManager() == this);
Debug.Assert(atsOuter == null || atsOuter.getAggregate() == agg.Parent, "");
if (typeArgs == null)
{
typeArgs = BSYMMGR.EmptyTypeArray();
}
Debug.Assert(agg.GetTypeVars().Count == typeArgs.Count);
Name name = _BSymmgr.GetNameFromPtrs(typeArgs, atsOuter);
Debug.Assert(name != null);
AggregateType pAggregate = _typeTable.LookupAggregate(name, agg);
if (pAggregate == null)
{
pAggregate = _typeFactory.CreateAggregateType(
name,
agg,
typeArgs,
atsOuter
);
Debug.Assert(!pAggregate.fConstraintsChecked && !pAggregate.fConstraintError);
pAggregate.SetErrors(false);
_typeTable.InsertAggregate(name, agg, pAggregate);
// If we have a generic type definition, then we need to set the
// base class to be our current base type, and use that to calculate
// our agg type and its base, then set it to be the generic version of the
// base type. This is because:
//
// Suppose we have Foo<T> : IFoo<T>
//
// Initially, the BaseType will be IFoo<Foo.T>, which gives us the substitution
// that we want to use for our agg type's base type. However, in the Symbol chain,
// we want the base type to be IFoo<IFoo.T>. Thats why we need to do this little trick.
//
// If we don't have a generic type definition, then we just need to set our base
// class. This is so that if we have a base type that's generic, we'll be
// getting the correctly instantiated base type.
var baseType = pAggregate.AssociatedSystemType?.BaseType;
if (baseType != null)
{
// Store the old base class.
AggregateType oldBaseType = agg.GetBaseClass();
agg.SetBaseClass(_symbolTable.GetCTypeFromType(baseType) as AggregateType);
pAggregate.GetBaseClass(); // Get the base type for the new agg type we're making.
agg.SetBaseClass(oldBaseType);
}
}
else
{
Debug.Assert(!pAggregate.HasErrors());
}
Debug.Assert(pAggregate.getAggregate() == agg);
Debug.Assert(pAggregate.GetTypeArgsThis() != null && pAggregate.GetTypeArgsAll() != null);
Debug.Assert(pAggregate.GetTypeArgsThis() == typeArgs);
return(pAggregate);
}
private bool TryVarianceAdjustmentToGetAccessibleType(CSemanticChecker semanticChecker, BindingContext bindingContext, AggregateType typeSrc, out CType typeDst)
{
Debug.Assert(typeSrc != null);
Debug.Assert(typeSrc.isInterfaceType() || typeSrc.isDelegateType());
typeDst = null;
AggregateSymbol aggSym = typeSrc.GetOwningAggregate();
AggregateType aggOpenType = aggSym.getThisType();
if (!semanticChecker.CheckTypeAccess(aggOpenType, bindingContext.ContextForMemberLookup))
{
// if the aggregate symbol itself is not accessible, then forget it, there is no
// variance that will help us arrive at an accessible type.
return(false);
}
TypeArray typeArgs = typeSrc.GetTypeArgsThis();
TypeArray typeParams = aggOpenType.GetTypeArgsThis();
CType[] newTypeArgsTemp = new CType[typeArgs.Count];
for (int i = 0; i < typeArgs.Count; i++)
{
if (semanticChecker.CheckTypeAccess(typeArgs[i], bindingContext.ContextForMemberLookup))
{
// we have an accessible argument, this position is not a problem.
newTypeArgsTemp[i] = typeArgs[i];
continue;
}
if (!typeArgs[i].IsRefType() || !((TypeParameterType)typeParams[i]).Covariant)
{
// This guy is inaccessible, and we are not going to be able to vary him, so we need to fail.
return(false);
}
CType intermediateTypeArg;
if (GetBestAccessibleType(semanticChecker, bindingContext, typeArgs[i], out intermediateTypeArg))
{
// now we either have a value type (which must be accessible due to the above
// check, OR we have an inaccessible type (which must be a ref type). In either
// case, the recursion worked out and we are OK to vary this argument.
newTypeArgsTemp[i] = intermediateTypeArg;
continue;
}
else
{
Debug.Assert(false, "GetBestAccessibleType unexpectedly failed on a type that was used as a type parameter");
return(false);
}
}
TypeArray newTypeArgs = semanticChecker.getBSymmgr().AllocParams(typeArgs.Count, newTypeArgsTemp);
CType intermediateType = this.GetAggregate(aggSym, typeSrc.outerType, newTypeArgs);
// All type arguments were varied successfully, which means now we must be accessible. But we could
// have violated constraints. Let's check that out.
if (!TypeBind.CheckConstraints(semanticChecker, null /*ErrorHandling*/, intermediateType, CheckConstraintsFlags.NoErrors))
{
return(false);
}
typeDst = intermediateType;
Debug.Assert(semanticChecker.CheckTypeAccess(typeDst, bindingContext.ContextForMemberLookup));
return(true);
}
private bool TryVarianceAdjustmentToGetAccessibleType(CSemanticChecker semanticChecker, BindingContext bindingContext, AggregateType typeSrc, out CType typeDst)
{
Debug.Assert(typeSrc != null);
Debug.Assert(typeSrc.isInterfaceType() || typeSrc.isDelegateType());
typeDst = null;
AggregateSymbol aggSym = typeSrc.GetOwningAggregate();
AggregateType aggOpenType = aggSym.getThisType();
if (!semanticChecker.CheckTypeAccess(aggOpenType, bindingContext.ContextForMemberLookup()))
{
// if the aggregate symbol itself is not accessible, then forget it, there is no
// variance that will help us arrive at an accessible type.
return false;
}
TypeArray typeArgs = typeSrc.GetTypeArgsThis();
TypeArray typeParams = aggOpenType.GetTypeArgsThis();
CType[] newTypeArgsTemp = new CType[typeArgs.size];
for (int i = 0; i < typeArgs.size; i++)
{
if (semanticChecker.CheckTypeAccess(typeArgs.Item(i), bindingContext.ContextForMemberLookup()))
{
// we have an accessible argument, this position is not a problem.
newTypeArgsTemp[i] = typeArgs.Item(i);
continue;
}
if (!typeArgs.Item(i).IsRefType() || !typeParams.Item(i).AsTypeParameterType().Covariant)
{
// This guy is inaccessible, and we are not going to be able to vary him, so we need to fail.
return false;
}
CType intermediateTypeArg;
if (GetBestAccessibleType(semanticChecker, bindingContext, typeArgs.Item(i), out intermediateTypeArg))
{
// now we either have a value type (which must be accessible due to the above
// check, OR we have an inaccessible type (which must be a ref type). In either
// case, the recursion worked out and we are OK to vary this argument.
newTypeArgsTemp[i] = intermediateTypeArg;
continue;
}
else
{
Debug.Assert(false, "GetBestAccessibleType unexpectedly failed on a type that was used as a type parameter");
return false;
}
}
TypeArray newTypeArgs = semanticChecker.getBSymmgr().AllocParams(typeArgs.size, newTypeArgsTemp);
CType intermediateType = this.GetAggregate(aggSym, typeSrc.outerType, newTypeArgs);
// All type arguments were varied successfully, which means now we must be accessible. But we could
// have violated constraints. Let's check that out.
if (!TypeBind.CheckConstraints(semanticChecker, null/*ErrorHandling*/, intermediateType, CheckConstraintsFlags.NoErrors))
{
return false;
}
typeDst = intermediateType;
Debug.Assert(semanticChecker.CheckTypeAccess(typeDst, bindingContext.ContextForMemberLookup()));
return true;
}
// Check the constraints of any type arguments in the given Type.
public static bool CheckConstraints(CSemanticChecker checker, ErrorHandling errHandling, CType type, CheckConstraintsFlags flags)
{
type = type.GetNakedType(false);
if (type.IsNullableType())
{
CType typeT = type.AsNullableType().GetAts(checker.GetErrorContext());
if (typeT != null)
{
type = typeT;
}
else
{
type = type.GetNakedType(true);
}
}
if (!type.IsAggregateType())
{
return(true);
}
AggregateType ats = type.AsAggregateType();
if (ats.GetTypeArgsAll().Count == 0)
{
// Common case: there are no type vars, so there are no constraints.
ats.fConstraintsChecked = true;
ats.fConstraintError = false;
return(true);
}
if (ats.fConstraintsChecked)
{
// Already checked.
if (!ats.fConstraintError || (flags & CheckConstraintsFlags.NoDupErrors) != 0)
{
// No errors or no need to report errors again.
return(!ats.fConstraintError);
}
}
TypeArray typeVars = ats.getAggregate().GetTypeVars();
TypeArray typeArgsThis = ats.GetTypeArgsThis();
TypeArray typeArgsAll = ats.GetTypeArgsAll();
Debug.Assert(typeVars.Count == typeArgsThis.Count);
if (!ats.fConstraintsChecked)
{
ats.fConstraintsChecked = true;
ats.fConstraintError = false;
}
// Check the outer type first. If CheckConstraintsFlags.Outer is not specified and the
// outer type has already been checked then don't bother checking it.
if (ats.outerType != null && ((flags & CheckConstraintsFlags.Outer) != 0 || !ats.outerType.fConstraintsChecked))
{
CheckConstraints(checker, errHandling, ats.outerType, flags);
ats.fConstraintError |= ats.outerType.fConstraintError;
}
if (typeVars.Count > 0)
{
ats.fConstraintError |= !CheckConstraintsCore(checker, errHandling, ats.getAggregate(), typeVars, typeArgsThis, typeArgsAll, null, (flags & CheckConstraintsFlags.NoErrors));
}
// Now check type args themselves.
for (int i = 0; i < typeArgsThis.Count; i++)
{
CType arg = typeArgsThis[i].GetNakedType(true);
if (arg.IsAggregateType() && !arg.AsAggregateType().fConstraintsChecked)
{
CheckConstraints(checker, errHandling, arg.AsAggregateType(), flags | CheckConstraintsFlags.Outer);
if (arg.AsAggregateType().fConstraintError)
{
ats.fConstraintError = true;
}
}
}
return(!ats.fConstraintError);
}
